#' @param features_col Features column name, as a length-one character vector. The column should be single vector column of numeric values. Usually this column is output by \code{\link{ft_r_formula}}.
#' @param label_col Label column name. The column should be a numeric column. Usually this column is output by \code{\link{ft_r_formula}}.
#' @param prediction_col Prediction column name.

